#include <stdio.h>

int main() 
{
    int a, b, c;
    0 < a < 1000;
    0 < b < 1000;
    0 < c < 1000;
    scanf("%d %d %d", &a, &b, &c);

    if(a + b > c && a + c > b && b + c > a)
    {
        if(a == b && b == c)  
        {
            printf("Equilateral triangle!");
        }
        else if (a == b || a == c || b == c)
        {
            printf("Isosceles triangle!");  
        }
        else
        {
            printf("Ordinary triangle!");
        }
    }
    else 
    {
        printf("Not a triangle!");
    }
    
    return 0;
}